Rhodotorula Glutinis: Strain Enrichment and Evaluation of Phenylalanine Ammonia Lyase

Abstract

The enrichment of a Rhodotorula glufinis strain and the determination of its phenylalanine ammonia lyase (E.C.4.3.1.5 - PAL) activity and attempts to measure peroxidase (E.C.1.11.1. 7) activity included conventional mycological procedures along with chemical and microscopic examination. Sabouraud dextrose medium was found to be the most suitable for cell growth, but cells grown on yeast-extract medium exhibited optimal enzyme activity. Growth and PAL activity were measured in yeast cells grown in yeast-extract broth medium for 24-27 h. The appearance of a reddish pink color associated with the yeast cells coincided with the appearance of appreciable PAL activity. The maximum PAL activity and biomass of yeast obtained in the yeast extract medium ranged from 33 to 35 unitslmg dry cells and 7.5 to 8.0 g dry cells/l, respectively. In addition to phenylalanine, Rhodatowla PAL also used phenylalanine methyl-ester as a substrate. No peroxidase activity was found in these R. glutinis cells.